Continuous, laminated-platen press for pressing glue-coated press charges

ABSTRACT

A continuous press for pressing glue-coated press charges includes a pair of cooperating press belts each comprising a pair of endless support members transversely mounting a plurality of press platens, with associated underlying anti-friction roller belts. Each press platen is of floating laminar construction. An endless caul belt overlies each press belt, arranged for protective contact with the press charge and preventing mutilation of its surface. A ratchet drive advances the belts in coordinated, step-wise increments determined by measuring means associated with the ratchet drive means and measuring the lineal progress of the work through the press. Side rolls guide the press belts as they travel the length of the press.

United States Patent 1191 Troutner Apr. 15, 1975 [75] Inventor: ArthurL. Troutner, Boise, Idaho [73] Assignee: Trus .loist Corporation, Boise,Idaho 22 Filed: Jan. 4, 1973 211 Appl. NO.C 320,874

Related [1.8. Application Data [63] Continuation-in-part of Ser. No.268,674, July 3, 1972, abandoned, Continuation-impart of Ser. No.79,839, Oct. 12, 1970, Pat. No. 3,723,230.

[52] US. Cl. 156/580; 100/151; 198/162; 425/371 [51] Int. Cl B30b 5/06;B30b 15/06 [58] Field of Search 156/580, 547; 425/371;198/162,165;100/151, 152,154,118

[56] References Cited UNITED STATES PATENTS 1,391,805 9 1921 Subers425/371 x 1,806,006 5/1931 Upson et al 100/118 2,602,960 7/1952Fischbein 156/580 X 3,064,590 11/1962 Thiele 425/371 3,082,859 3/1963Hagner et a1. 198/162 3,736,081 5/1973 Yovanich 425/371 X PrimaryExaminerCharles E. Van Horn Assistant ExaminerM. G. Wityshyn Attorney,Agent, or Firm-Eugene D. Farley [57] ABSTRACT A continuous press forpressing glue-coated press charges includes a pair of cooperating pressbelts each comprising a pair of endless support members transverselymounting a plurality of press platens, with associated underlyinganti-friction roller belts. Each press platen is of floating laminarconstruction. An endless caul belt overlies each press belt, arrangedfor protective contact with the press charge and preventing mutilationof its surface. A ratchet drive advances the belts in coordinated,step-wise increments determined by measuring means associated with theratchet drive means and measuring the lineal progress of the workthrough the press. Side rolls guide the press belts as they travel thelength of the press.

5 Claims, 19 Drawing Figures PATENTEUAPRISIBYS $878,027,

sum 3 of 3 FIG. 3

PATENTEDAFR 1 5:915 3,878,027

sum 5 0 2 w FIG. 8 9

62 36 m I32 I 130 ,ra9 1 114 ,1 18

% H8 l F I 2 h l i g I' l! w 4% Q :20 us CONTINUOUS, LAMINATED-PLATENPRESS FOR PRESSING GLUE-COATED PRESS CHARGES This application is acontinuation-in-part of the patent application of Arthur L. Troutner,Ser. No. 268,674, filed July 3, 1972 for CONTINUOUS, LAMI- NATED-PLATENPRESS FOR PRESSING GLUE- COATED PRESS CHARGES, now abandoned the samebeing a continuation-in-part of the patent application of Arthur L.Troutner, Ser. No. 79,839, filed Oct. 12, 1970 for CONTINUOUS PRESS FORPRESS- ING GLUE-COATED, CONSOLIDATABLE PRESS CHARGES, now US. Pat. No.3,723,230

BACKGROUND OF THE INVENTION This invention relates to continuous pressesfor pressing glue-coated, consolidatable press charges into a continuousproduct. It pertains particularly to a continuous press for glueingstacked glue-coated wood laminae into lumber or plywood and is describedwith particular reference to this application. No limitation thereby isintended, however, for the press is equally suitable for suchapplications as the consolidation of a mat of glue-coated wood particlesinto wood composition board.

In the aforesaid patent application of Arthur L. Troutner et al., Ser.No. 79,839, there is described a continuous press comprising essentiallya pair of elongated, vertically spaced press beds and a pair of endlesspress belts positioned between the press beds in substantial alignmenttherewith.

A pair of endless anti-friction belts are interposed between the pressbeds and the press belts in substantial alignment and in working contacttherewith. Drive means is connected to the press belts for advancingthem in the feed direction at a rate predetermined to effect a desiredconsolidation of the stack of wood laminae or other press charge duringsetting of the glue. At the same time, the working stretches of thepress belts are spaced a distance sufficient to exert a predeterminedpressure on the press charge passing in pressure contact between them.

The operation of this assembly leads to the production of a continuousplank or beam of indefinite length and having a width determined by thewidth of the press.

In the normal construction of such a press, the press beds and pressbelts comprise massive steel members. The anti-friction belts normallycomprise anti-friction roller belts, the rollers also being fabricatedfrom hard steel. Since the rollers of the anti-friction belts point loadthe press belts, very high pressures are developed at the interfacebetween these two components. The press belts accordingly are subject tocold working by the rollers on which they ride. This action takes placeon the roller side only of the press belts. On the opposite side, thecomponents are pressed uniformly against the press bed, which is ofsofter, flat material so that the unit pressures are lower.

The cold rolling effect causes the press belt components to cup as thecold worked surface expands and the opposite surface does not. Thecupped or curved surface in turn undesirably may imprint its contour onthe surface of the work passing through the press.

A further disadvantage of the cupping or curving of the press platensurfaces resides in the fact that the press belt elements do not lieflat on the underlying rollers. The curved faces touch only part of therollers,

thus increasing the roller pressure and magnifying the cold rollingeffect. This phenomenon occurs even at low pressure and in thick, hard,structural materials.

Another difficulty inherent in the operation of a press of this class,is that of guiding the work through the press in proper working relationto the parts of the latter. Specifically, the rollers of theanti-friction belts tend to skew as they progress through the press.This causes the associated press belts to shift in the direction of theskew, and thus to misalign the belts with reference to the press charge.

It accordingly is the object of the present invention to provide acontinuous press of the class described which is provided with pressbelts having platens permitting the inevitable cold working of theplatens to occur without interfering with their function.

Additional objects of the invention are the provision of a continuouspress of the class described fitted with continuous caul plates whichfurther prevent the disfigurement of the surface of the work, with meansfor guiding the press charge through the press in proper relation to thepress parts, and with an incremental drive of the accuracy necessary forthe production of a uniform product.

The continuous press of the present invention which achieves theforegoing objectives basically comprises a pair of elongated, verticallyspaced press beds associated with a pair of endless press beltspositioned be tween the press beds in substantial alignment. A pair ofendless anti-friction roller belts is interposed between the press bedsand the press belts in substantial alignment and in working contacttherewith. The working stretches of the press belts are spaced apart adistance sufficient to exert a predetermined pressure on aconsolidatable press charge passing in pressure contact between them.Drive means connected to the press belts advances them in the feeddirection at a rate predetermined to effect desired consolidation of thepress charge during setting of the glue.

Each press belt is comprised broadly of a pair of flexible endlesssupport members, such as endless chains, having a plurality of pressplates or platens supported transversely between them. Each press plateis of laminar construction. It consists of a relatively thick base plateand an overlying, relatively thin, cover or pressure plate. The coverplate is secured to the base plate in the central areas of both only.The ends of the cover plate are lightly confined and free to expand. Inthe operation of the press, the cover plate thus accepts the coldworking stresses without transmitting them to the base plate, which isin contact with the work. The base plate thus is not subject to adeformation which would be transferred to the press charge.

Further to protect the press charge there is included in the assembly apair of endless caul belts. One of these is interposed between eachpress belt and the press charge, therby preventing marring or scuffingof the surface of the latter. Also, an incremental drive of strictlycontrolled incremental magnitude is employed to further insureuniformity of the product.

Side guides are provided to guide the press belts, and the press charge,as they move through the press.

Considering the foregoing in greater detail and with particularreference to the drawings, wherein:

FIGS. 1 and 2 are fragmentary side elevations of the infeed and outfeedsegments of the herein described press, respectively, with parts brokenaway for convenience of illustration.

FIG. 3 is a transverse, fragmentary sectional view taken along line 33of FIG. 1.

FIG. 4 is a fragmentary plan view taken along line 4--4 of FIG. 3.

FIG. 5 is a fragmentary sectional view similar to FIG. 3, but showingadditional detail,

FIG. 6 is a fragmentary sectional view taken along line 66 of FIG. 1.

FIG. 7 is a fragmentary, plan sectional view taken on line 7-7 of FIG.1.

FIG. 8 is a foreshortened, plan, sectional view taken along line 8-8 ofFIG. 3 and illustrating a platen assembly employed in thehereindescribed press.

FIG. 9 is a transverse sectional view taken along line 9-9 of FIG. 8.

FIG. 10 is an exploded perspective view further illustrating the platenassembly.

FIG. 11 is a fragmentary side elevation illustrating the press drive.

FIG. 12 is a fragmentary section taken along line 12-12 of FIG. 11.

FIG. 13 is a fragmentary side elevation of the infeed segment of thepress illustrating the leading or forward guide roller locations, partsbeing broken away for convenience of illustration.

FIG. 14 is a diagrammatic, plan, foreshortened, fragmentary, sectionalview taken along line l4-l4 of FIG. 13.

FIG. 15 is a fragmentary, plan, sectional view taken along line l5l5 ofFIG. 13.

FIG. 16 is a fragmentary sectional view taken along line 16-16 of FIG.13.

FIG. 17 is a fragmentary elevational view taken along line 17-l7 of FIG.14.

FIG. 18 is a plan fragmentary sectional view taken along line 18-18 ofFIG. 17.

FIG. 19 is a fragmentary sectional view taken along line l9l9 of FIG.17.

THE PRESS CHARGE As has been indicated above, the presently describedpress may be applied to the consolidation and gluing of a variety ofpress materials. It may be applied in general to the continuous pressingof consolidatable press charges comprising matrices the components ofwhich are coated or impregnated with glue. Thus it may be applied to thecontinuous pressing of felts comprising mineral or woody particlescoated with glue, in the manufacture of composition boards.

The press is particularly applicable, however, to the pressing ofcharges comprising stacked, glue-coated wood laminae in the productionof lumber, heavy timbers, and plywood. The laminae advantageously maycomprise plywood veneers of any of the various commercial thicknesses.

In the preparation of the stacked laminae, the wood veneers or othersheets first are glue coated by any of the conventional technigues,i.e., by spraying, curtain coating, brushing, or roll coating.Sufficient glue is employed to fill any voids and coat the surfaces.Thermosetting or cold setting glues may be employed. To economize onpress length, it is preferred to employ quick setting glues.

The glue-coated laminae are laid up in a stack L. having a thickness,width, and pattern determined by the dimensions of the press and the enduse to which the pressed product is to be put. Thus the laminae may bestacked uniformly throughout the length of the charge to provide aproduct of uniform density throughout its length. On the other hand,where products of variable density are desired, the laminae may bestacked nonuniformly to provide areas which, after consolidation in thepress, are of greater density than the remaining areas of the pressedproduct.

DESCRIPTION OF A SPECIFIC EMBODIMENT However compounded, the presscharge is fed auto- The Press Beds The press beds with associatedstructural frame have for their primary functions supporting and backingup the press charge that moves continuously through the press whilebeing subjected to consolidating pressures. Their construction isillustrated particularly in FIGS. 1, 3 and 7.

The design of the framework supporting the press beds is such as to lendflexibility in size and application to the press. Thus the entire pressmay consist of a single module of thirty or more feet inlength. It is afeature of the invention, however, that the frame may be constructed ina plurality of modules to give a finished press having the desiredproduction and capacity.

In the particular embodiment of FIG. 7, the press, indicated generally10 and consisting of an upper section 10a and a lower section 10b, isdivided into an infeed module 12, one or more intermediate modules 14,and an outfeed module 16, all suitably connected as by means of flangedmembers and bolts 17.

Since heat is applied in the operation of the press, the frame ismounted to permit longitudinal thermal expansion. This is accomplishedby anchoring the infeed section of the press while permitting theintermediate modules to slide or float freely longitudinally.

To this end the infeed portion of the press is supported by a frameassembly which consists of anchor plates 16 secured to foundation 28 bythe usual means, and further secured to sub-frames 30 by means of anglebrackets 32 and bolts 34. A plurality of massive horizontally spacedvertical support bolts 36 are threaded All of the frame sub-assemblieshave a common design, as will be further described hereinafter, with theexception that bolts 36 supporting the infeed section of the press arespaced relatively close to each other for increased strength.

Bolts 36 and 48 clamp upper sleeves 50, intermediate spacers 52, andlower sleeves 54 to the sub-frames 30 and 42. Bridging between andintegral with matching pairs of sleeves 50 are lateral webs 56. At theirlower edges these support an upper, centrally disposed, longitudinallyextending bed plate 58. At their upper edges The Press Belts The pressbelts have for their function advancing the press charge through thepress, consolidating the press charge, and restraining the press chargeduring setting of the glue. Their construction is illustratedparticularly in FIGS. 1, 2 and 3.

The press belts each comprise a pair of endless flexible supportmembers, specifically heavy chains, transversely mounting a plurality ofpress plates or platens.

To support this assembly at the infeed end of the apparatus, there areprovided two pairs of bearing mounting brackets 72 bolted to the frameby bolts 74. Two pairs of bearings 76 are mounted to the bearingmounting brackets by means of bolts 78. .lournaled within these bearingsare a pair of transverse shafts 80. Keyed to the outer portions of theshafts by means of keys 82 are a pair of drive sprockets 84 onto whichis trained an endless drive chain 86.

At the outfeed end of the press, FIG. 2, a pair of slidable bearingblocks 88 journal cross shafts 90 which support two pairs of sprockets92. Each bearing block 88 has formed within its upper and lowerextremities a pair of vertically opposed bifurcated portions 94. Theseregister with and are supported by four pairs of rails 96.

To enable tensioning of the drive chains, bearings 88 are attached totensioning cylinders 97 through rams 98. The cylinders are mounted onintegral mounting ears 99 by means of bolts 100 and mounting lugs 101.

At their forward ends, rail pairs 96 are mounted detachably on crosswebs 56 and 62 by means of brackets 102 and bolts 103, 104. The rearwardportions of rail pairs 96 are detachably mounted to ears 105 which areintegrated with upper and lower sleeves 50, 54 respectively by means ofbolts 106.

The top links of chains 86 which are located in upper section a of thepress are supported by tracks 107. These in turn are integral with andsupported by webs 56, FIG. 6. The bottom links of chains 86, operatingin lower section 10b of the press, are supported by tracks 108, FIG. 3.Tracks 108 are pinned to the inner portion of sub-frames 30.

Continuously located throughout the length of drive chains 86 andforming the chain link hinge pivots are evenly spaced, inwardly disposedhinge pin extensions 109, FIG. 3. Transversely matching pairs of pins109 are journaled slidably and rotatably within bores 110 of platensupport blocks 111. Each platen support block has its inner cornersrelieved at 112 to provide the necessary clearance when changing thedirection of travel at the infeed and output ends of the press.

lnwardly facing slots 114 are formed within platen support blocks 111.These support opposing ends of transverse platens or press plates 116.The platens are detachably secured to the support blocks by a pair ofscrews 118.

By reference to FIGS. 1, 2 and 4, it will be noted that the arrangementof the platens is such that their adjacent, transverse edges are spacedclosely together when the platens are in their horizontal positionwithin the press.

As noted hereinabove, it is one of the features of the present inventionthat the platen construction is laminar in order to compensate for coldworking of one of its surfaces by the roller belt support with which itcomes in contact. This construction is apparent from a consideration ofFIG. 10.

A relatively thin pressure plate 124 is supported within slots 114 ofplaten support blocks 111. To permit its working under stresses, it isfastened to the platen in the center portion only. Thus it is mounted tothe inner surface 126 of the center portion of platen 116 by means of abar 128 and screws 130.

Bar 128 serves the purpose of attaching the platen pressure or coverplate to the platen. It also serves the purpose of a slide which tracksin a longitudinal guideway or rail 168 extending centrally the length ofthe press.

All four corners of cover pressure plate 124 have notches 132 whichregister with screws 118 and insure a floating arrangement of the coverplate ends. Located at the center of the cover plate are twotransversely opposed slots 14. These provide clearance for screws 130.Located at the center of platen 116 are two transversely opposed pockets135. These receive the projections 129.

The Anti-Friction Press Belts Means are included in the press assemblyfor minimizing the friction which otherwise would be present between themoving press belts, above described, and the stationary press beds. Themeans employed for this purpose comprise endless roller belts interposedbetween the press beds and press belts. The construction and manner ofoperation of these roller belts is illustrated particularly in FIGS. 1,2 and 3.

Shafts 80 additionally support inwardly mounted pairs of idler sprockets136, rotatably mounted on bearings 138 and integrated by tubes 140.Pairs of endless chains 142 are trained around the idler sprocketstraveling the complete length of the press. The chains terminate attensioning idler sprockets 144 mounted within the outfeed portion of thepress, FIG. 2.

Sprockets 144 are mounted rotatably on transverse shafts 146 which havetheir ends journaled within bearings 148. To enable tensioning of thechains, the rail pairs 96 above described slidably support and guidebearings 148 in the same manner as they slidably support and guidebearings 88.

A pair of tensioning cylinders 150 is attached to bearings 148 by meansof rams 152. Cylinders 150 are mounted by integral ears 154 and bolts156. These are threadably secured to mounting lugs 157 integral withrails 96.

Chains 142 have elongated hinge pins 158 extending inwardly and similarto hinge pins 108 on chains 86 heretofore mentioned. Pins 158 arejournaled within axially centered bores 160 located within each end 162of transverse pressure rollers 164.

Rollers 164 are made of hard steel and are responsible for the coldrolling action on the platens above described. The rollers have at theirmid-point grooves 166 which register with and receive platen rails 128,FIGS. 3 and 9.

Longitudinal primary guide rails 168 are supported centrally in grooves169 in bed plates 58 and 68. The rails register with and enter grooves166 of the pressure rollers 128, FIGS. 3 and 4. Slide bars 128 of theplatens also register with and enter grooves 166 of the rollers. In thismanner the press beds, press belts and antifriction belts are keyedtogether in operative relation, preventing lateral displacement of thebelts.

It will be noted from FIG. 1 that the upper surface 170 of bed plate 64generates into a ramp 172 at its forward end. A similar opposed surfaceis formed at the front portion of bed plate 58. As shown in FIG. 2, thelower surface 174 of bed plate 58 generates into a ramp 176 in itsterminal portion. The upper rear surface of bed plate 68 has an opposingsimilar surface. The front and rear portions of guide plates 60, 66 aresimilarly formed.

The upper horizontal runs of chains 142 that operate within upper presssection a are supported and guided by an upwardly extending pair oflongitudinal tracks 180. These are intergral with guide plates 60, FIG.6. The bottom horizontal run of chains 142 that operate within lowersection 1012 or the press are guided by a pair of longitudinal,downwardly extending tracks 182. These are integral with guide plates66, FIG. 3.

The Endless Cauls It is a further feature of the instantly describedpress that not only is the surface of the press charge protected fromthe defacing action of malformed, coldrolled press plates, but also fromscratching and marring caused by contact with any of the elements of thepress. To this end, endless steel caul belts optionally but preferablyare interposed between the press charge and the pressing elements.

As is shown in FIGS. 1-4, a pair'of endless spring steel belts 220 arelocated in the upper section 10a and the lower section .1012 of thepress. At the infeed end, the belts 220 are trained around platens 116.

Rearwardly, they are trained around rollers 222 which are supported bytransverse shafts 244. The shafts have their ends journaled withinbearing blocks 226 which are slidably mounted between rails 96 in amanner similar to the manner of mounting bearings 88 and 148, previouslydescribed. The bottom run of belt 220 located in press section 1012 issupported by a plurality of rollers 237.

Pairs of tensioning cylinders 228 are connected to bearings 226 by meansof rams 230. Cylinders 228 are demountably secured by integral flanges232 and bolts 234. The latter are threaded into lugs 236 which in turnare integral with rails 96.

Tensioning cylinders 228, like tensioning cylinders 97, 150 abovedescribed, have an independent fluid supply source which will deliverfluid at a pressure suiting the requirements of the tensioning system.

The Press Belt Drive The inner horizontal runs of drive chains 86 aredriven by one or more sets of four chain driving ratchets indicatedgenerally at 22. These are located transversely in pairs in the upperand lower, and terminal and central sections of the press.

Each drive unit consists of a carriage 238 formed by a pair of plates240, FIGS. 11 and 12. The plates are positioned in spaced relation by apair of washers 242. The latter in turn are positioned by a pair ofclamping bolts 244 located at both ends of carriage 238.

Bolts 244 also position two pairs of support rollers 246 that extendoutwardly from plates 240. The rollers travel within inwardly disposedlongitudinally guideways 248. These are formed within pairs of tracks250 detachably mounted by means of bolts 252 to the frame plates 254.The latter are integral with the longitudinal frame web 68 and at theirinner portions and supported by clamping bolts 48 and sleeves 255 attheir outer portions.

A pair of rollers 256 are journaled onto two stub shafts 257 which areintegral with plates 240 and are positioned within relieved portions 258located on the right hand end of the carriage 238. The peripheries ofthe rollers extend slightly beyond the outer surfaces 260 of plates 240and engage the inner surfaces 264 of tracks 250. This effectively guidescarriage 238 in the transverse direction.

Carriages 238 are driven by cylinders 263 with rams 264, spreadablysecured within a connector guide 266. The latter in turn is secured tothe carriage 238 by a bolt 244. It forms part of the connector guide266. Guide portions 267 extend toward and contact chains 86.

Cylinder 262 is anchored by pin 268 and ears 270 the latter beingintegral with upper and lower webs 56 and 62 respectively.

Positioned between plates 240 are a pair of chainroller-engaging ratchetpawls 272. These are mounted rotatably on cross pins 274 secured toplates 240 in the usual manner. Extensions 276 are formed on the caulsand when in chain driving position bear against stop pins 278. Thelatter are secured to plates 240.

Mounted to the extensions 276 at 280 are tension springs 282 anchored onpins 284 formed on plates 240.

The ratchet drive serves to move the press charge incrementally alongthe length of the press, on a timed sequence determined by the pressloading schedule and arrangement, the glue setting time and otherconsiderations. A problem is presented in maintaining the increments atprecisely the right value, particularly in view of the variable stretchof each of the four chains 86, resulting in failure of the pawls toregister accurately with the particular chain rollers they seek toengage. Accordingly, a system is employed that will controlindependently each of the four ratchet units 22 so that it can make anappropriate compensation.

Referring to FIG. 2, a spring loaded, linear, measuring wheel 290 ofconventional construction contacts the upper surface of the finishedlaminate. It is supported by a linear control unit 292 mounted'to frame38 at its outfeed portion. The total design stroke of ram 264 is greaterthan the incremental stroke that is re quired.

FIG. 11 illustrates the ram in retracted position while at rest. It alsoillustrates the ratchet pawl 272 in a typical rest position relative tothe chain rollers. When the ram begins its extension, carriage 238 willtravel a certain distance until the ratchet pawl contacts the chainroller 289. Subsequent movement of the press charge then will initiatethe rotation oflinear measuring wheel When the associated measuring unit292 determines the desired increment of travel of the press charge, themeasuring unit operates to halt the stroke of ram 264 through anassociated electric circuit. Thereupon the ram returns to its retracted,at rest position, ready for a new stroke. Consequently, regardless ofthe position of the pawl relative to chain rollers 289, the laminatetravel will start only at the precise movement when pawl 272 initiallycontacts the roller causing the chain to move simultaneously with thepress charge.

As an adjunct of the apparatus, heating means are provided to supplyheat in sufficient amount to set the adhesive and/or plasticize thepress charge, thereby assisting in the final consolidation of thecharge. Suitably disposed and designed heaters are applied to thispurpose. In the illustrated form of the invention, a plurality ofheaters 286 are secured by bolts 288 to the outer surfaces of bed plates58 and 68 at strategic locations along the length of the press.

As a further important adjunct of the press, there is provided means forcontrolling the thickness of the product. Such means comprises one ormore substantial clamps indicated generally at 23 positioned in criticallocations along the length of the press. Each clamp consists of upperand lower transverse bars 316, 318. These bear respectively against bedplates 58 and 68. They are held together in adjustable relation by theaction of a pair of clamping bolts 320. Since they back up the bedplates, they act as effective stops against which the press charge ispressed, thereby determining its final thickness.

FIGS. 13-19 illustrate a form of the invention in which guide meansisprovided for assisting in the longitudinal guiding of the press beltsas they move through the press.

As noted above, a difficulty inherent in the operation of a press of theclass described herein is that of guiding the press belts through thepress in such a manner as to maintain the work in proper workingrelation to the press elements. Specifically, the rollers of theantifriction belts tend to skew as they progress through the press. Thiscauses the associated press belts to shift in the direction of the skewand thus to misalign the belts with reference to the press charge.Because of the great length of the press, and the high pressuredeveloped, this effect may occur to some degree in spite of the factthat the press beds, press belts and antifriction belts are keyedtogether in the manner already described.

Accordingly, there are provided in the press of the invention guidemeans for insuring that the press belts, anti-friction belts and chargewill not stray from their predetermined paths through the press. In theillustrated form of the invention, the guide means comprises guideroller assemblies indicated generally at 321, 322 respectively.

As shown particularly in FIGS. 13-16, guide roller assemblies 321 arelocated in the infeed portion of the press. Each comprises a hardenedsteel roller 323 rotatably mounted on a pair of bearings 324. Thebearings are journaled within recesses 326 located centrally of therollers.

A cross shaft 328 is journaled within bearings 324. It has its outerends pressed into bores 330 located within outwardly extendingsupporting blocks 332. The latter are integral with a pair of supportingarms 334. Pins 336 secure shaft 328 to blocks 332.

Support arms 334 are mounted for pivotal movement on a cross shaft 338.The latter is journaled in pairs of mounting ears 340. These areintegral with spacers 52. Pins 342 retain the cross shaft.

Means are provided for adjusting the position of the rollers relative tothe press belts.

Bearing against blocks 332 are the ends of a pair of adjustment bolts344. These are threaded into a pair of supporting bars 346. Thesupporting bars in turn are integral with, and bridge, adjacent sleeves52. Lock nuts 348 retain the bolts.

As shown in FIGS. 14, l7, l8 and 19, guide roll assemblies 322 includinghardened steel guide rollers 350 of larger diamenter are employedthroughout the rest of the length of the press. This is possible becausedownstream from the infeed portion of the press, where the preliminaryalignment occurs, the guide rolls may be spaced farther apart. It isimportant to use rolls of as large diameter as is practical in order toincrease the bearing surface and avoid deformation of the platen parts.

To mount rollers 350, a pair of bearings 354, FIG. 17 is journaledwithin a bore 352 formed within each each roller. Journaled withinbearings 354 is a cross shaft 356 which has its ends pressed withinbores 358 formed within a bifurcated support arm 360.

A pair of spacing rings 362 are positioned on the shaft and bridge thegap between bearings 354 and arms 360. Clips 363 retain the outer endsof cross shaft 356.

One end of support arm 360 is hinged to the structural bolt member 36,thereby facilitating maintenance and bearing replacement.

For this purpose there is formed a vertical bore 364 through one end ofthe support arm. A bushing 366 is rotatably mounted within the bore. Thebushing is secured to structural bolt member 36 by being clamped betweentwo adjacent sleeves 368.

The vertical dimension of the end of support arm 360 is slightly lessthan the vertical dimension of bushing 366. This provides a slightclearance 370.

The opposite end of support arm 360 is retained adjustably by means of apair of studs 372 which are integral with sleeves 368. Studs 372 extendthrough slots 374 formed within one end of support arm 360. They mountpairs oflock nuts 376 on the outer threaded portions. When rollers 350are not positioned adjacent one another, as illustrated in thedownstream end of FIG. 14, studs 372 are integral with sleeves 52.

The location of the guide roller assemblies in the press is ofimportance in determining their proper functioning. In the infeed zone,before singificant pressures are applied to the press charge, the chargeis initially guided and centered by closely spaced, compact, guideroller assemblies 321. Immediately downstream from the infeed zone is azone where maximum pressures are applied to the press charge, whichaccordingly is somewhat over-consolidated. Maximum guiding is requiredin this zone. Accordingly, there are provided a plurality of guideroller assemblies 322 in closely spaced arrangement.

Downstream from the over consolidation zone the press pressure becomesprogressively less thus requiring progressively fewer guide rollerassemblies of the class indicated at 322. Wherever located, the guideroller assemblies 321 and 322 are mounted in opposing pairs to minimizedistortional stresses.

During operation of the press the peripheral surfaces of guide rollers323 of assemblies 321 and guide rollers 350 of assemblies 322 bearagainst the outer end surfaces of platen support blocks 111, as shownparticularly in FIGS. 13 and 19. The arrangement is such that thehorizontal center lines of rollers 323 and 350 are substantially alignedwith the mating surfaces 113 of platen support blocks 111. A properworking relationship may be maintained by adjustment of bolts 344 andstuds 372.

The adjustment of the rollers should be such that those at the infeedend of the press, where heavy pressure has not as yet been applied tothe press charge, are in direct contact with platen support blocks 111.On the other hand, in the downstream zones where heavy pressure isapplied, a slight but predetermined clearance should be present betweenthe rollers and the platen support blocks. Effective guidance of thepress belts thus is obtained at all times, uniformly along their entirelength and in spite of the very heavy pressure developed in the press.

OPERATION The operation of the hereindescribed continuous press is asfollows:

At the infeed end of the press a continuously fed, unconsolidated,adhesive coated laminate L is fed to the press manually or, preferably,by an automatic machine that assembles individual wood veneers into anassembly having a predetermined pattern of staggered veneer laps. Theoutermost lamina does not have adhesive on its outer surface.

The press belts driven by ratchet assemblies 22 drive the press chargethrough the press in predetermined increments of travel. As the chargepasses through the press, it is subjected to great pressure exerted bythe platens of the press belts, backed up by the press bed plates andintervening antifriction roller belt.

The cold rolling effect of the rollers of the antifirction belt againstthe press platens 126 is dissipated by the partially floating coverplates 124 which cover the platen back surfaces and absorb the deformingpressure. They are replaceable upon deformation. Marring of the surfaceof the work by the press belt components is prevented by the action ofthe intervening caul belts 220 interposed between the platen faces andthe work. Control of the final thickness of the glued laminate isachieved by clamp units 23 incorporating clamp bars 316, 318 which actas stops against which the charge is pressed. The accuracy of theincremental drive is insured by control of the ratchet cylinders bymeasuring instrument 292. Proper guidance of the press belts, and henceof the press charge, is achieved by the action of guide roll assemblies321, 322 as they bear against the ends of the individual press platenscomprising the belts.

Accordingly, there is discharged from the outfeed end of the press, aconsolidated, laminar, continuous lumber product L which in a typicalinstance may be three or 4 inches thick, 3 or 4 feet wide, and ofindefinite length. This is trimmed and cut to billets of the desiredlength with an edger and cut-off saw. Thereafter, the billets arereduced further in size to form such products as beams, dimensionlumber, cords for trusses, and other lumber items.

Having thus described my invention in preferred embodiments, I claim:

1. In a continuous press for pressing glue-coated press charges andincluding central longitudinal guide means and a pair of cooperatingpress belts each comprising a pair of laterally spaced endless supportmembers transversely mounting a plurality of press platens. a laminatedpress platen comprising:

1. a base plate,

2. means connecting the ends of the base plate to the respective endlesssupport members,

3. a cover plate overlying the working face of the base plate, and

4. fastening means fastening the cover plate to the base plate,

5. the fastening means comprising a transverse bar secured across thecentral portion of the cover plate and having slide means dimensionedfor reception in the guide means.

2. The laminated press platen of claim 1 wherein the cover plate isfastened to the central portion only of the base plate, the cover plateends being unrestrained.

3. The assembly of claim 1 including a pair of endless caul belts oneoverlying the plates of each press belt and arranged for protectivecontact with the press charge.

4. The assembly of claim 1 wherein the endless support members compriseendless chains and including ratchet drive means therefor comprising atleast one ratchet positioned for engaging each chain, a variable strokefluid operated cylinder connected to the ratchet, measuring meansengaging the press charge surface for measuring its lineal travelthrough the press, and cylinder control means interconnecting themeasuring means and the cylinder and operative to arrest the cylinderstroke at a distance commensurate with a predetermined lineal travel ofthe press charge.

5. In a continuous press for pressing glue-coated press charges andincluding a pair of cooperating press belts each comprising a pair ofendless support emmbers transversely mounting a plurality of pressplatens, a laminated press platen comprising:

1. a pair of end blocks having slots in their opposed inner faces,

2. a base plate with its ends received in the slots,

3. a cover plate overlying the working face of the base plate with itsends received in floating condition in the slots,

4. a bar mounted transversely across the central portion of the coverplate and secured releasably to the base plate,

5. releasable securing means securing the blocks to the ends of the baseplate, and

6. releasable securing means securing the blocks to their respectiveendless support members.

1. In a continuous press for pressing glue-coated press charges andincluding central longitudinal guide means and a pair of cooperatingpress belts each comprising a pair of laterally spaced endless supportmembers transversely mounting a plurality of press platens, a laminatedpress platen comprising:
 1. a base plate,
 1. a pair of end blocks havingslots in their opposed inner faces,
 2. a base plate with its endsreceived in the slots,
 2. means connecting the ends of the base plate tothe respective endless support members,
 2. The laminated press platen ofclaim 1 wherein the cover plate is fastened to the central portion onlyof the base plate, the cover plate ends being unrestrained.
 3. Theassembly of claim 1 including a pair of endless caul belts one overlyingthe plates of each press belt and arranged for protective contact withthe press charge.
 3. a cover plate overlying the working face of thebase plate, and
 3. a cover plate overlying the working face of the baseplate with its ends received in floating condition in the slots,
 4. abar mounted transversely across the central portion of the cover plateand secured releasably to the base plate,
 4. fastening means fasteningthe cover plate to the base plate,
 4. The assembly of claim 1 whereinthe endless support members comprise endless chains and includingratchet drive means therefor comprising at least one ratchet positionedfor engaging each chain, a variable stroke fluid operated cylinderconnected to the ratchet, measuring means engaging the press chargesurface for measuring its lineal travel through the press, and cylindercontrol means interconnecting the measuring means and the cyLinder andoperative to arrest the cylinder stroke at a distance commensurate witha predetermined lineal travel of the press charge.
 5. In a continuouspress for pressing glue-coated press charges and including a pair ofcooperating press belts each comprising a pair of endless supportemmbers transversely mounting a plurality of press platens, a laminatedpress platen comprising:
 1. a pair of end blocks having slots in theiropposed inner faces,
 2. a base plate with its ends received in theslots,
 3. a cover plate overlying the working face of the base platewith its ends received in floating condition in the slots,
 4. a barmounted transversely across the central portion of the cover plate andsecured releasably to the base plate,
 5. releasable securing meanssecuring the blocks to the ends of the base plate, and
 6. releasablesecuring means securing the blocks to their respective endless supportmembers.
 6. releasable securing means securing the blocks to theirrespective endless support members.